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Scale problem

  1. Jan 22, 2004 #1
    We have a helicopter flying and use the power "P" to keep it in equilibrium. But if the scale was greater n times, what would be the power to keep it there?
     
  2. jcsd
  3. Jan 24, 2004 #2
  4. Jan 24, 2004 #3
    Thanks, but didn't need such detail. I thought that if the scale was greater n times then the volume of the helicopter had to be proportional to n^3. So with the same density, its mass also had to be proportional to n^3.
    [tex]
    P= \Delta W/t
    [/tex]

    [tex]
    P=F \Delta x/t
    [/tex]

    [tex]
    P=mg \Delta x/t
    [/tex]

    So if m increases n^3 times, P must increase n^3 times and the new power would be n^3P.
    Was I wrong?

    for latex.
     
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